Boiler superheater



Dec. 16, 1952 J. W. THROCKMORTON ETAL BOILER SUPERHEATER Filed March 8, 1949 FIG 2 lNVENToRs. -JOHN W. THROGKMORTON JOHN S. WALLIS ATTORNEY.

FIG.|

Patented Dec. 16, 1952 BOILER SUPERHEATER John W. Throckmorton and John S. Wallis, New York, N. Y., assignors to Petro-Chem Process Company Incorporated, New York, N. Y., a corporation of Delaware Application March 8, 1949, Serial No. 80,174

2 Claims.

This invention is an improvement on the boiler construction disclosed in Patent No. 2,375,505, issued May 8, 1945, to Throckmorton et al.

An object of the invention is to increase the efficiency of the boiler by adding a superheater which may be in the form of a bank of tubes located in the lower part of the furnace between the furnace wall and the regular water tubes of the boiler.

Further and other objects and advantages will be apparent from the specification and claims, and from the accompanying drawings which illustrate what is now considered to be a preferred embodiment of the invention.

In the drawings:

Fig. 1 is a cross-section of the boiler showing the superheater of the invention; 7

Fig. 2 is a cross-section on line 2-2 of Fig. l; and

Fig. 3 is a cross-section on line 33 of Fig. l but with parts of the outer shell and insulating lining broken away.

The structure comprises a shell In lined with insulation I2 and supported on structural steel legs l4.

Below floor I6 is an annular manifold is, and rising from that manifold is the usual ring of water tubes 20, the upper, bent ends of which terminate in steam drum 22.

Extending downwardly from drum 22 is a downpipe 24 passing through fioor I6 and resting in a cup 26 which is supported by channels 28 attached to the underside of the floor.

Closely surrounding pipe 24 and resting on floor I6 is a tubular sleeve 30 supporting a conical bafile 32, which is extended upwardly in the form of a cylindrical tube 34 of proper diameter to form an annular convection zone between tube 34 and insulation I2. Within that convection zone water tubes 20 are provided with heat absorbing fins or other extended surfaces 36.

Below floor l6 downpipe 24 is connected to manifold 18 by radial tubes, as at 38.

Radiant heat is supplied by burners 40 set in fioor 16 (Figs. 1 and 2) and the products of combustion, guided by bafile 32-34, pass out through stack 42.

The stack is supported by a structural steel framework 44 mounted on the tops of legslll.

2 Framework 44 also carries a bracket 46 fitted around the top of drum 22 in order to hold the drum in place.

Drum 22 is supplied with clean-out openings as at 48.

The steam after entering drum 22 from tubes 20 passes downwardly around tubular baffle 50 within drum 22 and then upwardly-through the bafile, leaving drum 22 through purifier 52, outlet pipe 54 and thence through downpipe 56 to enter annular manifold 58 which supports a bank of superheater tubes 66 between the main water tubes 20 and the insulation wall 12 of the furnace.

The number of superheating tubes, their lengths, and their distribution, may vary according to the amount of superheat desired, the

quantity of steam, and other conditions.

In Fig. 3 a complete circle of tubes 60 is indicated, with a divided, or Z-pass flow, half to the right and half to the left as indicated by arrows. However, a limited number of tubes may be used, with their lengths designed to meet required conditions. The flow may be as shown, but may be series or multi-pass, depending on circumstances such as quantity, pressure drop, and other conditions.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claims.

We claim:

1. In a boiler including a vertical cylindrical combustion chamber having a lower radiant zone and an upper convection zone, a ring of vertical water tubes extending through both said zones, a steam drum located substantially within said convection zone and having a downpipe connected to the bottom thereof for water circulation, means connecting the tops of said water tubes to said steam drum near the top of the drum, a sleeve covering said downpipe and having a conical baffle joined thereto, a cylindrical bafile at the top of said conical bafile and forming said convection zone, a superheater comprising an annular manifold surrounding said water tubes, a pipe connecting said manifold with said steam drum, and a ring of superheater tubes connected to said manifold and positioned between said water tubes and the wall of said com- 4 bustion chamber within said radiant zone, in REFERENCES CITED order to partially screen the superheater tubes The following references are of record in the from the radiant heat of the furnace. H of thi atent:

2. The combination as set forth in claim 1 1 e s p wherein said annular manifold is divided into two 5 UNITED STATES PATENTS sections, and. having two pipes connecting said Number Name Date sections with the steam drum, the ring of super- 365,347 Malcolm June 21, 1887 heater tubes being divided into two banks, said 1,737,173 Pratt Nov. 26, 1929 pipes connecting the manifolds with the steam 1,881,275 Hufi Oct. 4, 1932 drum being positioned outside the combustion 10 1,896,233 Gordon Feb. 7, 1933 chamber. 1,975,503 Engler Oct. 2, 1934 JOHN W. THROCKMORTON. 2,043,095 De Florez June 2, 1936 JOHN S. WALLIS. 2,276,527 Throckmorton et a1. Mar. 17, 1942 

